The invention pertains to high production bead seating and inflation apparatus for tubeless tires.
The seating and inflation of pneumatic tires on a high production basis has necessitated the development of specialized equipment for this purpose, and various types of apparatus have been proposed to accomplish bead seating and inflation in a minimum of time, and with a minimum of supervision and manual operations. Accordingly, a number of devices have been produced for seating and inflating tubeless tires on their associated wheel wherein such operations may be accomplished automatically without direct supervision.
In order to achieve high production bead seating and inflation it has been recognized that the introduction of air into the tire by means other than through the valve stem located in the wheel would substantially reduce the duration required for inflation. Accordingly, devices are known wherein inflation of the tire occurs prior to seating of one tire bead with its associated wheel rim, and devices of this type are shown, for instance, in U.S. Pat. Nos. 2,779,397; 3,461,938 and 3,528,474. However, difficulty has been experienced with devices disclosed in the aforementioned patents in maintaining adequate sealing between the apparatus and the wheel and tire over extended periods of time due to wear of the sealing surfaces and edges resulting in inconsistent inflation and an excessive use of compressed air.
In the applicants' prior U.S. Pat. No. 3,461,938, a piston is lowered to sealingly engage the upper rim of a wheel upon which a tubeless tire had been placed. The piston is supported by vertically movable apparatus wherein the wheel rim is contacted while on a conveyor, and at a station wherein wheel movement ceased. A cylinder mounted upon the same support as the piston includes a lower edge which engages the upper sidewall of the tubeless tire, and is spring biased downwardly with sufficient force to unseat the upper sidewall and upper bead from the upper wheel rim to maintain spacing therebetween. Compressed air introduced between the upper tire bead and wheel rim inflates the tubeless tire, and during the final stages of inflation the cylinder is moved upwardly by the pressure within the tire permitting the bead to seat on the wheel rim.
The aforementioned apparatus of the applicant, while performing satisfactorily, requires periodic replacement of the sealing means upon the piston and cylinder, and this apparatus had limitations with respect to its use with large sizes of tubeless tires, such as truck tires.